Ok guys I have a 04 coupe headlights quit working have been to 2 certfied mechanics we have checked grounds,fuses and tried 4 headlight modules Turn them on they close and lights come on,turn them off lights raise n go off,We have tried cycling the motors manually and disconnecting battery to reset.They've checked contacts used scanners to check everything and so far everything has worked we are at a loss.

 

Someone with more knowledge will chime in but check all four bump stops to see if they're worn down. If so just flip them over and see if that resolves your issue. I'm by no means an expert at the symptoms but I do know when you put your headlights down and they come back up many times it's the bump stop that is the culprit. It's worth a shot.

 

Sorry, can't help. But I just finished servicing the driver's side headlight motor with a gear change, re-installed, and motor doesn't work. Checked plug in, fuse, removed, re-inspected, have 12 volts at brushes. Maybe when someone chimes in I can learn something too.

 

I'll check them tomorrow thanks a lot

 

What exactly are the issues? Nothing happens at all or do the go up and down but not light. We need a little more info.

 

yeah is it the headlight or the housing itself? So you turn the headlights on and the buckets raise but lights go off and when you close the buckets the lights go on? Your post is a little confusing boss

 

Okay hopefully I can help you. Did you remove your headlight arm off the motor for any reason?

A couple of days a go, I rebuilt one of my headlight motors. I took the complete headlight assembly out. After I rebuilt the motor and reinstalled it, the side I had serviced was acting exactly like yours.

One side would function perfectly, the other side would do the complete opposite. After troubleshooting for a bit I realized I had incorrectly installed the arm that actually raises the headlight doors. Basically I had the arm installed backwards, so it would actually lower the headlights instead of raising them.

Hopefully I've been of help and that's also your problem. If you ever unbolted your headlight motors or disassembled the raising arm, most likely that's your problem.

Good luck and let us know what you figure out.

 

The headlights when turned on lower but the lights come on,when you turn them off they raise but the lights go off,nothing has been taken off but the module to change it out,We have tried 4 different modules.

 

That's exactly what happens sorry it was confusing

 

As RXPX stated it's possible the attachment point for the control arm needs to be rotated 180 degrees. Did this just start happening out of the blue or were any parts of the headlight disassembled or anything like that prior to this occurring?

 

Just happened out of the blue,i had changed a turn signal bulb then all of this started transpiring,Makes no sense it has 2 GM certified mechanics going bonkers trying to figure it out.

 

Yes, that's what my headlight door was doing when it was incorrectly positioned.

I would turn the headlight switch on and the bucket would close, but the headlight bulb would come on. If I turned the headlight switch off, the bucket would lift/raise/open, but the headlight bulb would turn off.

You said it all started after a turn signal bulb replacement? That's definitely strange. I'm having a hard time understanding how a bulb replacement could change the wiring circuitry. Maybe make sure the bulb is correctly installed, or try a different bulb, heck, reinstall the old bulb and see what that does.

Someone else mentioned to make sure and check the bump stops. Another possibility could be the bump stops were so worn out, the arms went past their operating points and somewhat reversed them selves? Also, I know this is a little obvious but make sure the headlight connectors are installed correctly along with the headlight module connectors.

I noticed you said you've had techs check for power. Have they checked for voltage/signal at the respective locations? On the headlight connector, one wire signals for the buckets to 'raise', another wire signals to 'lower' the buckets, one wire powers on the bulb, one is ground and I can't remember the rest. If the headlight switch is on, and there is signal at the correct respective wires/pins, I'm again leaning towards the raising arm being positioned incorrectly. You really can't tell their on there wrong without having a correctly installed arm to compare to.

If you can, post a picture of the way your arms are sitting on the bump stops.

If you absolutely cannot figure it out, I can only thing of 2 somewhat 'fixes'.

1. Switching the Raise/Lower wires in the headlight connector.

2. Purposely switching the raising arms over so it lifts the bucket the opposite way.

I know some of these ideas are far fetched but just trying to think what could be wrong without being there.

 

I'm totally at a loss the bumpstops look new I tried the bulb change and nothing so guess maybe I will do like you said and reverse the wires and see what happens

 

Sorry for the late reply, I'm sure we'll figure this out.

Before you switch the wires, upload a picture showing how your arms are sitting on the bumpstops. Hopefully we can make some progress from there.

 

Ok I'll try to get pictures tomorrow weather permitting I really appreciate the help

 

No problem, I'll check the thread tomorrow.

 

The arm on the motor should swing around to the front of the car as it opens the headlight. It's hard to get a good view in a picture without removing the shroud. Also, on the cases I've seen with the arm backwards the headlight door would only open part way. But, if the arms did go past the stops then pull the bumpers off the stops and install some washers between the motor and the bracket until the arms will hit the metal stop the bumper sticks onto.

I'd wonder if the MFS is messed up and not sending the correct signal anymore. There is a dark green wire at the headlight module that should have power when the switch is off.

Also, no amount of manually cycling the headlights will change anything. There are no stops or limit switches in the motors. The motors are just a simple 2-wire assembly that the module powers in each direction.

I wouldn't just reverse the motor wires because that could cause it to switch back if the real problem is corrected.

 

Ok I'll check that wire and go from there,Nothing was removed so I really don't think it's the arms but I'll double check them,Any ideas on a function check on the MFS??

 

Do you have the twilight sentinel option? Try that and see what it does. It will bypass the multifunction switch.

 

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